Resin compositions of urethane resins, acrylic resins and the like are divided into solvent-based systems which use organic solvents to provide good film formability and water-based systems which, due to concerns over environmental contamination, do not include organic solvents. Owing to concerns over organic solvents evaporating in the drying step and adversely affecting worker health, solvent-based resin compositions most often use high-boiling organic solvents such as N,N′-dimethylformamide (DMF).
Artificial leathers and synthetic leathers that have been internal addition treated or surface treated with a solvent-based or water-based resin composition are used in such applications as automobile seats, furniture and apparel, and are desired to have gloss, slippage and leveling ability. Highly polymerized polydimethylsiloxanes are included so as to satisfy the need for slippage and wear resistance. In order to be able to include polydimethylsiloxanes both in solvent-based resin compositions and in water-based resin compositions, emulsification or the like must be carried out to enable the polydimethylsiloxane to disperse both in DMF and in water. However, when a polydimethylsiloxane emulsion composition obtained by emulsification with a nonionic surfactant, an anionic surfactant or a cationic surfactant is included in a DMF or other solvent-based resin composition, it does not uniformly disperse, as a result of which an emulsified state cannot be maintained and the polydimethylsiloxane separates out. Accordingly, there has existed a desire for the development of highly polymerized polydimethylsiloxane emulsion compositions that are capable of dispersing in both solvents such as DMF and in water.
Emulsion compositions that are stable to solvents have hitherto been developed. Patents relating to emulsion compositions which include polar solvents such as alcohols are described below.
Patent Document 1: JP No. 3023250 discloses an oil-in-water type emulsion cosmetic containing a cyclic silicone, a surfactant, a highly polymerized pendant polyoxyalkylene-modified silicone, ethanol and titanium oxide. A polyoxyalkylene-modified silicone in which silicone side chains are modified with short-chain polyoxyalkylene groups is used, which differs in structure from that of the polyoxyalkylene-modified organopolysiloxane compound included in the emulsion composition of the present invention. Also, an emulsion composition of a cyclic silicone is mentioned, and so the object of this art is not the emulsification of a highly polymerized organopolysiloxane.
Patent Document 2: JP No. 3417567 discloses an emulsion of an oil and a lower alcohol obtained with a pendant polyoxyalkylene-modified silicone. By using a pendant polyoxyalkylene-modified silicone as the emulsifying agent, the emulsion is stable even when it includes a high concentration of alcohol. This art uses a polyoxyalkylene-modified silicone having silicone side chains modified with short-chain polyoxyalkylene groups, which silicone differs in structure from the polyoxyalkylene-modified organopolysiloxane compound included in the emulsion composition of the present invention. Also, emulsion compositions in which the base oil is a liquid paraffin, a higher alcohol, a silicone oil or the like are given as examples, and so the object of this art is not the emulsification of highly polymerized organopolysiloxanes.
Patent Document 3: JP No. 3633820 discloses an emulsion which is intended for use as a cosmetic and includes a polysiloxane obtained from a polyoxyalkylene-modified silicone that is modified at both ends, a powder treated for water repellency, and ethanol. Because the emulsion composition of the present invention does not include a treated powder, the compounding ingredients are different. Also, emulsion compositions containing cyclic siloxanes and 6 cs low-viscosity polysiloxanes as the base oil are mentioned as examples, and so the object of this art is not the emulsification of highly polymerized organopolysiloxanes.
Patent Document 4: JP No. 5646355 discloses an emulsion which is intended for use as a cosmetic and includes a polydimethylsiloxane, a polyether-modified silicone and a lower alcohol. The polydimethylsiloxane has a viscosity of from 20 to 10,000 mm2/s, which differs from the viscosity of the organopolysiloxane of the present invention.
In addition, patents relating to resin compositions obtained by formulating urethane resin compositions for artificial leather or synthetic resin with polydimethylsiloxanes are described.
Patent Document 5: JP-A 2014-80713 discloses the formulation of a solid dimethylsilicone in a urethane resin, and the use of the resulting composition as a surface treatment agent for synthetic resins. A non-emulsified dimethylsilicone is used, and appears to be incapable of being blended into a water-based resin composition. Accordingly, this does not disperse in solvent-based or water-based resin compositions, and so this art differs from the emulsion composition of the present invention.
Patent Example 6: JP-A 2007-314919 discloses a water-based resin composition which includes, together with a urethane resin: a polyisocyanate crosslinking agent, a silicone compound and a filler. The silicone compound is a polyether-modified silicone. Hence, this art differs from the emulsion composition of the present invention which is obtained by emulsifying a highly polymerized organopolysiloxane.
In addition, a patent relating to a paint that includes a polydimethylsiloxane and a polyalkylene-modified organopolysiloxane is described.
Patent Example 7: JP 5186079 discloses a paint additive which is a mixture of a silicone modified at one end with a polyether and a nonionic surfactant, which can persistently impart a slight degree of hydrophilicity to the surface of a coating film, and the purpose of which is to exhibit an ability to prevent fouling by aquatic organisms over an extended period of time. The present invention was developed with the object of imparting slippage and wear resistance to synthetic resins, artificial resins and the like used in automobiles and bags. Hence, the art described here differs from the present invention both in its makeup and in the intended use.